Compiles ES6+

[wolovim]

What does it do?

Adds the ability to write ES6+ features in electron (async/await, module imports, etc.)

Any helpful background information?

• The .compilerc file is picked up by the electron-compile and can be further tweaked. See: https://github.com/electron/electron-compile#how-do-i-set-up-babel--less--whatever-the-way-i-want
• Implementation updated to use a simpler configuration with Babel.
• In menuItems.js, devtToolsSubMenu was never instantiated with const or let, so I did to resolve a new error I received.
• There's a small async/await example in main.js to verify nothing explodes while testing.

Which code should the reviewer start with?

Small diff. Take it from the top.

New dependencies? What are they used for?

• electron-compile & electron-compilers to JIT compile ES6+ within electron. See: https://github.com/electron/electron-compile
• babel-gulp for prod transpiling
• babel-register for dev transpiling
• babel-preset-es2016 - es7 preset

[evertonfraga]

Message from CI:

Unhandled rejection Error: Error: Application entry file "entry.js" in the "/home/travis/build/ethereum/mist/dist_mist/dist/linux-unpacked/resources/app.asar" does not exist. Seems like a wrong configuration.

[wolovim]

@evertonfraga yup - whoops. Didn't have all the build steps accounted for (and tools installed); waiting through that now. Will update when finished 😎

[evertonfraga]

No problem. Broken CIs are a good thing :)

I can take a look at this tomorrow morning, don't worry.

[evertonfraga]

I feel way more comfortable with babel rather than electron-compiler.